A man's feet should be planted in his country, but his eyes should survey the world.

We must welcome the future, remembering that soon it will be the past; and we must respect the past, remembering that it was once all that was humanly possible.

Eternal vigilance is the price of knowledge.

The mass of mankind is divided into two classes, the Sancho Panza's who have a sense for reality, but no ideals, and the Don Quixote's with a sense for ideals, but mad.

Christianity persecuted, tortured, and burned. Like a hound it tracked the very scent of heresy. It kindled wars, and nursed furious hatreds and ambitions... Man, far from being freed from his natural passions, was plunged into artificial ones quite as violent and much more disappointing.

I feel so much the continual death of everything and everybody, and have so learned to reconcile myself to it, that the final and official end loses most of its impressiveness.

Man alone knows that he must die; but that very knowledge raises him, in a sense, above mortality, by making him a sharer in the vision of eternal truth. He becomes the spectator of his own tragedy; he sympathizes so much with the fury of the storm that he has no ears left for the shipwrecked sailor, though the sailor were his own soul. The truth is cruel, but it can be loved, and it makes free those who have loved it.